In modern data processing systems, or computers, an operating system manages the distribution of system resources to various processes benefiting the user, such as, for example, user-interfaces accepting specific tasks from the user or higher-level applications providing more complex benefits. Processes running in a user space (or application space) do not have permission to utilize the system's resources on their own. Operating systems provide entry points through system calls, which may be implemented using software interrupts, that allow user-level processes to request services from the kernel. Thus, these processes make predefined calls to the operating system to request resources from the operating system. The processes may be configured to make calls directly or by making calls to an application program interface (‘API’) which implements system calls. System calls and API calls may be implemented differently on various operating systems, or on different versions of the same operating system.